Low-lying darters speak volumes about the health of Southern Appalachian rivers.
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By fish standards, most are small, only an inch or two long, and, because they tend to hang out at the bottom of fast-flowing creeks and streams, they can be hard to spot. They’re also some of the most beautiful freshwater fish in the Blue Ridge region, often named for their striking colors: blueface, vermillion, bridled, the latter sporting a pattern that resembles a horse’s headgear. Stabilized by large pectoral side fins, they can maneuver the water like Olympic superstar Katie Ledecky and move so quickly they’re hard to catch, hence the name darter.
“The Southeast is home to more darter species than just about anywhere else on the planet,” says Will Harlan, Southeast director and senior scientist at the Center for Biological Diversity in Asheville, North Carolina. “We’re blessed with an abundance of water, so we have an abundance of darter species.”
Unfortunately, like many native inhabitants of the Appalachians, they’re also at risk of being wiped out. Harlan estimates that between 30% and 40% of darter species are significantly declining.
“And that’s real cause for concern. They play a really important role in keeping our rivers clean and are also indicators of the health of rivers. That’s why, as we’re seeing all these declines in our darters, we’re concerned about what that means for our drinking water and for human communities.”
Despite the proliferation of species, most are limited to a specific, small place. “If you destroy just a single stream or tributary, you can set that species spiraling toward extinction,” Harlan says. “So a lot of them are in trouble.”
Wikipedia | Noel Burkhead
The greatest threat, Harlan points out, is sedimentation from development, pollution and dams. “They can’t live in areas that are filled with sediments,” Harlan says. “It clogs their breathing and feeding mechanisms, so they can’t survive. And we’ve seen that play out in some really noteworthy species.”
In Virginia and West Virginia, for example, the candy darter has been “hammered” by pollution and sedimentation that frequently stems from pipeline construction, Harlan notes. Only 35 tiny populations still exist in all of Appalachia. Likewise, the sickle darter, a bronze-hued species once found throughout the southern part of the mountain range, has been reduced to six small geographical areas in southern Virginia and eastern Tennessee.
The good news, says Harlan, is that more people are rediscovering — and appreciating — darters as they venture into rivers, creeks and streams, a trend that began with the pandemic. The Blue Ridge Snorkel Trail, made up of curated sites in the North Carolina mountains, guides nature lovers to some of the best spots for darter-watching up close. Dams that have fallen into disrepair are coming down, freeing the fish and other aquatic critters to move up- and downstream. Wildlife agencies and nonprofit groups are working to remove out-of-service dams and restore natural waterways. Thanks to a 2023 U.S. Fish and Wildlife ruling, for example, 104 miles of critical sickle darter habitat are now protected under the Endangered Species Act.
“Many of these darter species are five million years old,” says Harlan. “They were here way before us, and they’ve been inhabiting these streams for millennia. The least we can do is give them a chance at survival.”
The story above first appeared in our November / December 2025 issue. For more like it subscribe today or log in with your active BRC+ Membership. Thank you for your support!